Shellfish from Maine have been recalled after samples tested positive for high levels of a dangerous neurotoxin.

The recall notice, issued by the Maine Department of Marine Resources, applies to mussels and mahogany quahogs (another name for clams) that were harvested or wet-stored in the Jonesport area between September 25 and September 30; as well as clams harvested between Cranberry Point in the town of Corea to Cow Point in Roque Bluffs between September 28 and September 30.

As the Portland Press Herald reports, the samples tested contained an unsafe amount of domoic acid. Domoic acid-tainted shellfish can cause amnesic shellfish poisoning in humans. In severe cases, the poisoning may lead to neurological symptoms like short-term memory loss, disorientation, seizures, even death.

Jeff Nichols, a spokesperson for the Department of Marine Resources, told the Herald that no cases of illness have been reported.

The phytoplankton that produce domoic acid have existed off the coast of Maine for decades, he said. When shellfish consume the phytoplankton, the toxin can accumulate in their systems. But this is the first time Maine shellfish have been found to have harmful levels of the toxin.